15 Exhibit 12.1 Boston Edison Company Computation of Ratio of Earnings to Fixed Charges Twelve Months Ended March 31, 1997 (in thousands) Net income from continuing operations $137,278 Income taxes 85,429 Fixed charges 117,567 -------- Total $340,274 ======== Interest expense $108,319 Interest component of rentals 9,248 -------- Total $117,567 ======== Ratio of earnings to fixed charges 2.89 ====